1. Field of the Invention
The present invention generally relates to a method of and an apparatus for processing citrus peel, and more particularly it concerns a method of and an apparatus for separating citrus peel into its flavedo and albedo fractions.
2. Description of the Prior Art
As is well known, many uses have been found for the albedo and flavedo portions of the citrus peel. For example, the albedo fraction of the citrus peels has been used for its dietary fiber value, as a clouding agent in beverages and as a filler material in the preparation of pet food. A use for the flavedo fraction has been as a coloring agent in the preparation of foodstuffs. Uses for by-products of citrus peel are indicated in the following patents: U.S. Pat. No. 3,647,475, which indicates that the albedo fraction can be used in a finely divided form as a clouding agent in citrus fruit juice; U.S. Pat. No. 2,708,627, wherein it is stated that the flavedo fraction is a satisfactory source of carotene and xanthophyll and that the albedo fraction may be used to fortify stock foods; U.S. Pat. No. 3,239,359, which indicates that the albedo fraction is useful in making animal feeds and as an additive for the production of a cereal for human consumption; U.S. Pat. No. 2,452,750, which states that the albedo fraction is an extremely rich source of protopectin which, when converted into a water-soluble pectin, can be used as a supplemental food product for human consumption; U.S. Pat. No. 3,868,466, which discloses a method for dehydrating and treating whole citrus peels to produce a food additive; U.S. Pat. No. 2,186,907, which describes a method of making a dried citrus food product which is especially suited for animal feed and possibly also for human food and wherein the peel, seeds and rag of citrus fruit are ground and screened to form a thick paste which is thereafter dried and flaked; and U.S. Pat. No. 2,976,159, which discloses the use of the albedo fraction to produce a carrier for food flavors. It will thus be appreciated that citrus peels have been commercially processed into a variety of food products for a long period of time.
The only previously known method for separating citrus peel into its flavedo and albedo fractions is by shaving or peeling the flavedo fraction from the albedo fraction. A shaving method of separating peel is subject to several problems. First, there is no clear line of demarcation between the colored flavedo portion and the white albedo portion of citrus peel. Thus, in order to obtain an albedo fraction which is sufficiently free from flavedo, it is necessary to set the shaving or peeling apparatus to either cut deeply through the outer flavedo layer and well into the albedo layer or, vice versa, to cut only a thin layer of the albedo from the peel. This results in a wasting of the portion of the albedo which remains attached to the separated flavedo fraction.
Another problem arises as a result of the condition in which the peel is provided to the peeling or shaping apparatus. When whole half peels are to be handled, it will be appreciated that it will be relatively easy to orient the peel with the flavedo and albedo portions in an orientation such that the flavedo or the albedo may be removed from the remaining part. However, much of the in-line juice extraction equipment now used in the citrus juice industry does not produce a whole half peel, but rather produces masses of randomly oriented, shredded and crumpled peel segments. An example of an extraction apparatus which will produce the latter type of peel produce is disclosed in U.S. Pat. No. 2,649,730, issued in 1953 to J. M. Hait. As shown and described in this patent, the extractor includes upper and lower cups adapted to interdigitate as the upper cup is plunged downwardly. The fruit is received in the lower cup, and, as the cups come together, the juice is extracted and simultaneously the peel is crumpled and partially shredded and expelled in such condition from the extractor. Peel in such condition is randomly oriented during discharge and is not readily susceptible to separation by a shaving method.